Roentgenium

Symbol: RgAtomic number: 111Category: transition metalsGroup: 11Period: 7Block: dAtomic weight: [280] g/molElectrons per shell: 2, 8, 18, 32, 32, 17, 2CAS number: 54386-24-2Phase: presumably a solidDensity: unknownMelting point: unknownBoiling point: unknownCrystal structure: unknownOxidation states: 3 (expected)Electronegativity: unknownName's origin: RöntgenName's meaning: the German physicist Wilhelm Conrad Röntgen
Facts:- is a synthetic element
- its most stable known isotope has a mass of 283 amu and an estimated half-life of ten minutes
- was found by Peter Armbruster, Gottfried Münzenberg, and their team working at the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany on December 8, 1994, but the IUPAC/IUPAP Joint Working Party (JWP) concluded that there w for the discovery at that moment in time
- the GSI team repeated their experiment in 2000 and detected a further 3 atoms, and in their 2003 report, the JWP decided that the GSI team should be acknowledged as the discoverers